Vibrating feeders with frequency and amplitude controls



Jul 13, 965 L, E. MYLTING 3,194,445

VIBRATING FEEDER WITH FREQUENCY AND AMPLITUDE CONTROLS Filed Feb. 12. 1963 m m "u "h "I H 11404 77 Z 6. MVZ 7711/6 BY I United States Patent 3,l%,445 VIBRAIING FEEDER WETH FREQUENCY AND AMPLITUDE QGN'IRQLS Lauritz E. Mylting, Ardmore, Pa, assignor, by mesne assignments, to Buell Engineering Company, inc, Lebanon, Pa, a corporation of Delaware Filed Feb. 12, 1963, Ser. No. 257,967 6 Claims. (Ci. 222 199) This invention relates generally to the art of handling finely divided solids and is particularly concerned with means for vibrating a hopper wall or reciprocable feeder and with means for varying the rate and amplitude of the vibrations of the vibrator.

Heretofore, means have been provided for vibrating one or more walls of a hopper to facilitate the flow of the fine solids out of the hopper and means has also been provided for vibrating or reciprocating means below a hopper which controls the flow of fine solids therefrom. Each of these Vibrating means included means for varying the frequency of the vibrations, or for varying the amplitude of the vibrations, or for varying the frequency and amplitude simultaneously. However, so far as I know, no prior vibrating means has been provided in which the frequency and amplitude of vibrations could be varied independently of one another and in predetermined relation to one another; nor in which a plurality of vibrators could be controlled by a single means for simultaneous vibration and for synchronous variation in frequency, amplitude and independent simultaneous variation in amplitude and frequency relative to one another.

Since there are many instances in which it is desirable to vary either the frequency or the amplitude of one vibrator separately or in predetermined relation to one another, and also many instances in which it is desirable to actuate a plurality of vibrators in synchronism and to be able to vary the amplitude and frequency simultaneously of all the vibrators by a single means, the present invention aims to provide apparatus for such uses. That aim is achieved by the new combination of elements disclosed herein.

In the drawings, FIGURE 1 is a diagrammatic view partly in section showing one form of apparatus embodying the present invention;

FIGURE 2 is a vertical central longitudinal section through a feeder equipped with the vibrator means of FIGURE 1;

FIGURE 3 is a transverse sectional view taken on line 3-3 of FIGURE 2;

FIGURE 4 is a longitudinal cross-sectional view of the vibrator; and, 7

FIGURE 5 is a diagrammatic view showing a system embodying the present invention in which a single valve is used in the actuation of a plurality of feeders on separate hoppers.

FIGURE 1 shows at 1 a portion of a hopper for finely divided solids and 2 designates a housing which partly encloses a feeder. The means for vibrating the feeder includes a cylinder 3 and a piston which is freely reciprocable therein. Fluid carrying lines 5' and 6 lead from the ends of cylinder 3 to a four-way valve '7. This valve comprises a cylinder 8, a piston 9 reciprocable therein and a piston rod 10 provided with a cam roller 11 to follow cam 12. A fluid carrying line 15 connects the interior of cylinder 8 with a main fluid pressure line 16. A control valve 17 serves to control the flow of fluid through line 15 and is actuated in response to impulses or signals in line 18 which may be given manually, mechanically or automatically. Fluid carrying line 2d connects the main inlet line 16 with an air motor 21.

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This motor drives cam 12 by means indicated at 22. A valve 25 serves to control the flow of fluid through line Zti to the air motor, and this valve is actuated in response to impulses or signals given manually, mechanically or automatically by signal line 26.

It will be understood that when valve 17 is open, air may flow from the main line 16 through line 15 and into the four-way valve 8 thence into one end or the other of cylinder 3 depending on the position of piston 9 in cylinder 3. When valve 25 is open, the air motor 21 will rotate cam 12 and reciprocate the piston 9 in cylinder 8. When the piston 7 moves to its uppermost position, as seen in FIG. 1, air from line 15 may flow past piston 9 and into and through pipe 5 thereby propelling piston 4 toward the left end of cylinder 3. At the same time fiuid in the left end of the cylinder may escape through line 6 into cylinder 8 below piston 9 and thence to the atmosphere. When piston 9 moves down far enough to shut off the flow of fluid into pipe 5, fluid will flow through line 15 past piston 9 and into line 6, and piston 4 will be moved to the right end of cylinder 3, fluid in that end of cylinder 3 escaping through line 5 and cylinder 8 to the atmosphere.

It will be understood that the greater the flow of fluid through valve 25 to the air motor, the more rapidly it will be actuated and the more rapidly piston 9 will be reciprocated. Thus, by varying the rate of flow of fluid through valve 25, the frequency of the vibrations of the feeder caused by piston 4 will be correspondingly varied. The amount of fluid admitted into the ends of cylinder 3 determines the amplitude of movement of the feeder caused by piston 4, the larger the amount of fluid so admitted, the greater will be the impact of the piston at the ends of its stroke and the greater will be the extent of movement of the feeder.

It will be noted that valves 17 and 25 may be independently adjusted. As a result, the amplitude of movement of the feeder may be varied by adjusting valve 17 while the frequency of reciprocation of the feeder remains constant; or by adjusting valve 25 the frequency may be varied while the amplitude remains constant; and by adjusting both valves, both amplitude and frequency may be varied with, or relative to, one another.

The present invention will be better understood by reference to FIGURES 2 to 4 in which the feeder housing 2 and the feeder 3d are shown in vertical section. The housing 2 is a generally box-shaped housing having vertical sides, an open bottom and a downwardly inclined passage 31 defined by inclined walls 32 and 33 and substantially vertical side walls 34. A gate 35, generally arcuate-shaped, serves to close the lower end of passage 31 and is carried by plates 36 secured to the ends thereof and arms 37 pivoted for swinging movement on trunnions 33 attached to the outer sides of walls 34. A shaft 4-6 mounted in bearing 41 in one side wall of the housing 2 is attached at its inner end to one arm 37 and is provided with a lever 45 by means of which the gate 35 may be moved into, and out of, position closing the lower end of passage 31.

The lower end of passage 31 extends through the top of a feeder 30. This feeder or pan has generally horizontal top and bottom walls 5t and 51 and parallel inclined ends 52 to which the lower ends of leaf springs 53 are attached, the upper ends being attached to the housing 2. By reason of this spring suspension of the feeder or pan 30, it may be reciprocated short distances in opposite directions. At its forward end, bottom wall 51 of pan 35) is cut away so that solids fed into the pan from passage 31 may be moved to, and discharged through, this opening which is indicated at 55" in FlIG- URE 2.

A vibrator is shown at the left of FIGURE 2 attached to the inclined end 52 of the pan near opening 55. This vibrator is shown in more detail in FIGURE 4. There, a cylinder 69 is clamped between two end blocks 61, and is connected to end wall 52 of the pan, as by bolts 62 and nuts 63. Within cylinder 60 is mounted a free, multipart piston designated in its entirety by numeral 65. This free piston has end pieces 66 between which a threaded rod 67 and nuts 68 clamp a plurality of weighted discs 69.

Each end block 61 is provided with a space 72 and a passage 73 and these spaces communicate with the valve 8 through lines 5 and 6 which are screwed into the threaded portions of passages 73. The end pieces 66 of piston 65 are provided with guiding projections 75 which move into adjacent spaces 72 at the ends of the stroke of the piston, and strike the opposed face of the end piece.

It will be understood that when fluid under pressure is admitted into one end block, for example the right hand end block in FIGURE 4, the piston will be moved toward the left end block and when the opposite end piece of the piston engages the adjacent block 6 1, an impact force Having thus described this invention in such full, clear, concise and exact term-s as to enable any person skilled in the art to which it pertains to make and use the same, and having set forth the best mode contemplated of carrying out this invention, I state that the subject matter which I regard as being my invention is particularly pointed out and distinctly claimed in what -is claimed, it

' being understood that equivalents or modifications of, or

substitution-s for, parts of the above spec'ifically'described embodiment of theinvention may be made without departing from the scope of the invention as set forth in what is claimed.

will be delivered to the latter with the result that the I feeder pan will be urged in one direction. When the fluid is delivered into the other end block, the piston travel will be reversed, an impact blow will be delivered to the other end block and the feeder pan will be reciprocated in the opposite direction. As the feeder pan reciprocates, solids will be fed out of passage 31 when the gate 35 is open and will be discharged through opening 55 in the bottom wall of that pan.

It will be understood that as the valve 17 is adjusted to increase the amount of fluid which is discharged into the ends of the cylinder 3, the impact force which the free piston 4- delivers to the end pieces of the cylinder will be increased, and that as these impact forces are increased, the length of travel of the feeder pan will increase. Thus, by adjusting valve 17 to increase or decrease the amount of fluid discharged into the end of cylinder 3, the amplitude of movement of the feeder pan may be increased or decreased.

It will also be understood that when valve 25 is adjusted so as to increase or decrease the rate of movement of the air motor 21 and the resultant rotation of cam 12, the rate of frequency of reciprocation of piston 9 in the four-way valve 7 will be increased or decreased, and the frequency with which fluid is admitted into the opposite ends of cylinder 3 will increase or decrease. Thus, the valve 17 controls the amplitude of reciprocation of the feeder pan while the valve 25 controls the rate of reciprocation of that pan. Since valves 17 and 25 are independent .and may be independently adjusted, the amplitude of the feeder pan can be varied independently of the frequency and the frequency can be varied independently of the amplitude. Thus, the amplitude'and frequency may be varied independently of one another or in any predetermined relation to one another.

In FIGURE 5 is shown the invention embodied in a plurality of hoppers like the one shown in FIGURE 1 and designated at 1. Each of these hoppers has a feeder and vibrator like theparts shown at 2 and 3 in FIGURE 1. The cylinders 3 of each of the several hoppers are connected to a single valve 7 so that air under pressure may be simultaneously admitted into the corresponding ends of the several cylinders. The four-way valve 7 may be controlled and actuated by the mechanism shown in FIGURE 1. I

The vibrating mechanism disclosed above for vibrating or. oscillating the feeders of hoppers may also be used for vibrating a wall of one or more hoppers, as shown in FIG. 5, to facilitate the feeding of solids out of the hoppers, To that end, vibrators of the types shown in FIG. 1' or FIG. 4 are attached to as many of the walls of one or more hoppers as are to be vibrated. Obviously, if desired, the hopper wall vibrators may be used in the absence of the feeder vibrators of FIG. 5.

What is claimed is:

1. A feeder for feeding finely divided solids which comprises a feeder pan, means to deliver fine solid-s into said pan, means suspending the pan from said housing for limited reciprocation in opposite direct-ions, means for reciprocating said pan, said means including a cylinder attached tosaid pan, a free piston in said cylinder, and means for admitting high pressure 'fluid alternately into opposite ends of said cylinder, mean-sfor varying the amplitude of reciprocation of the pan including a valve for controlling thevolume of said fluid admitted'into said. cylinder, and means for varying the frequency of reciprocation of said pan including a reciprocable piston controlling the flow of said fluid to said cylinder and mechanical means to reciprocate said reciprocable piston.

2. A feeder for feeding divided solids which comprises a feeder housing having a downwardly inclined passage for fine solids, a gate controlling the flow of solids out of said passage, a feeder pan positioned to receive solids from said passage, means suspending the pan from said housing for limited reciprocation in opposite directions, means for reciprocating said pan and feeding solids therefrom, said means including a cylinder attached to said pan and a piston reciprocable in said cylinderto deliver impact blows to said cylinder and means for varying the amplitude and frequency of reciprocation of said pan, said means including conduits for high pressure fluid, a

'valve for varying the volume of flow of 'such fluid into the ends of the cylinder, a reciprocating piston for alternately directing the flow of said fluid into the ends of said cylinder, and mechanical means controlled by said fluid for varying the rate of reciprocation of said reciprocating piston. V

3. A feeder for feeding finely divided solids which comprises a feeder housing having a downwardly inclined passage for fine solids, a gate pivotally supported'by said housing and movable into and out of position to open or close the lower end of said passage, a feeder pan en closing the lower end of said passage to receive solids therefrom and having a bottom opening remote from said passage, springs suspending the pan from said housing for reciprocation in a generally horizontal path, and means for vibrating said pan, said means including a cylinder attached to said pan, a free pistonin said cylinder, a fourway valve including a reciprocable piston, conduits connecting the ends of said cylinder, to said valve for admitting fluid alternately into opposite ends of the cylinder to reciprocate the free piston therein and thereby apply forces to the pan to reciprocate it, means including'a cam and cam follower to actuate said reciprocable piston, an air motor connected to the cam t-o rot-ate it, a main line for fluid under pressure, a first branch line connecting the main line to said air motor, a second branch line connecting the main line to said four-way valve, valves in said branch lines to control the. flow of fluid through the latter, and means to adjust the valves and thereby to vary the flow of fluid through said branch lines.

4. A feeder for feeding finely divided solids which comprises a reciprocable feeder pan, a vibrator for reciprocating said pan, including a cylinder attached to said pan, a free piston in said cylinder and means for admitting high pressure fluid alternately into opposite ends of said cylinder, means for varying the amplitude of reciprocation of the pan including a valve for controlling the volume of said fluid admitted into said cylinder, and means for varying the frequency of reciprocation of said pan including a reciprocable piston controlling the flow of said fluid to said cylinder, and means for varying the rate of reciprocation of said reciprocable piston.

5. A feeder for feeding finely divided solids which comprises a fine solids hopper including a movable wall, a vibrator connected to said wall and including a cylinder, a free piston in said cylinder and means for admitting high pressure fluid alternately into opposite ends of said cylinder, means for varying the amplitude of reciprocatiOn of the piston in the cylinder including a valve for controlling the volume of said fluid admitted into said cylinder, and means for varying the frequency of reciprocation of said piston including a reciprocable piston for controlling the flow of said fluid to said cylinder, -a cam to move the reciprocable piston and means to rotate said cam at variable speeds.

6. A feeder for feeding finely divided solids which comprises a fine solids hopper including a vibra-table wall, a vibrator connected to said wall and including a cylinder, a free piston in said cylinder and means for admitting high pressure fluids alternately into opposite ends of said cylinder, means for varying the volume of said fluid admitted into said cylinder, and means for varying the frequency of reversal of flow of said fluid to said cylinder including a cylinder, a reciprocable piston therein and means for varying the rate of reciprocation of said piston.

References Cited by the Examiner UNITED STATES PATENTS 2,740,561 4/56 Coffman 222-200 X FOREIGN PATENTS 220,346 8/57 Australia.

SAMUEL F. COLEMAN, Primary Examiner.

LOUIS J. DEMBO, Examiner, 

3. A FEEDER FOR FEEDING FINELY DIVIDED SOLIDS WHICH COMPRISES A FEEDER HOUSING HAVING A DOWNWARDLY INCLINED PASSAGE FOR FINE SOLIDS, A GATE PIVOTALLY SUPPORTED BY SAID HOUSING AND MOVABLE INTO AND OUT OF POSITION TO OPEN OR CLOSE THE LOWER END OF THE SAID PASSAGE, A FEEDER PAN ENCLOSING THE LOWER END OF SAID PASSAGE TO RECEIVE SOLIDS THEREFROM AND HAVING A BOTTOM OPENING REMOTE FROM SAID PASSAGE, SPRINGS SUSPENDING THE PAN FROM SAID HOUSING FOR RECIPROCATION IN A GENERALLY HORIZONTAL PATH, AND MEANS FOR VIBRATING SAID PAN, SAID MEANS INCLUDING A CYLINDER ATTACHED TO SAID PAN, A FREE PISTON IN SAID CYLINDER, A FOURWAY VALVE INCLUDING A RECIPROCABLE PISTON, CONDUITS CONNECTING THE ENDS OF SAID CYLINDER TO SAID VALVE FOR ADMITTING FLUID ALTERNATELY INTO OPPOSITE ENDS OF THE CYLINDER TO RECIPROCATE THE FREE PISTON THEREIN AND THEREBY APPLY FORCES TO THE PAN TO RECIPROCATE IT, MEANS INCLUDING A CAM AND CAM FOLLOWER TO ACTUATE SAID RECIPROCABLE PISTON, AN AIR MOTOR CONNECTED TO THE CAM TO ROTATE IT, A MAIN LINE FOR FLUID UNDER PRESSURE, A FIRST BRANCH LINE CONNECTING THE MAIN LINE TO SAID AIR MOTOR, A SECOND BRANCH LINE CONNECTING THE MAIN LINE TO SAID FOUR-WAY VALVE, VALVES IN SAID BRANCH LINES TO CONTROL THE FLOW OF FLUID THROUGH TE LATTER, AND MEANS TO ADJUST THE VALVES AND THEREBY TO VARY THE FLOW OF FLUID THROUGH SAID BRANCH LINES. 